<b>Elevated C-Reactive Protein Levels and Increased Cardiovascular Risk in Patients With Obstructive Sleep Apnea Syndrome</b>

Abstract

SUMMARYObstructive sleep apnea syndrome (OSAS) is associated with cardiovascular morbidity and mortality. Inflammatory processes associated with OSAS may contribute to cardiovascular morbidity in these patients. C-reactive protein (CRP) is an important serum marker of inflammation. We tested the hypothesis that patients with OSAS have increased plasma CRP.After 173 male subjects underwent polysomnography, 94 were considered to have OSAS (apnea-hypopnea index (AHI) > 5), 38 cardiovascular disease (CVD), and 56 without CVD. Seventy-nine subjects were considered not to have OSAS (AHI < 5) and from among these 57 patients without CVD were enrolled as control subjects.Serum CRP levels were significantly elevated in the OSAS + CVD group compared to the two other groups (P < 0.05). When we evaluated the association between the serum CRP level and severity of OSAS, CRP levels were positively correlated with AHI in OSAS patients (r = 0.61, P < 0.001) OSAS, as a marker of inflammation and cardiovascular risk, is associated with elevated levels of CRP. According to these results, the link between cardiovascular morbidity and OSAS may be explained by the coexistence of other cardiovascular risk factors such as circulating CRP levels. (Int Heart J 2005; 46: 801-809) Key words: CRP, Sleep apnea, Inflammation OBSTRUCTIVE sleep apnea syndrome (OSAS) is a common disorder that affects both children and adults. It is characterized by periods of breathing cessation (apnea) and periods of reduced breathing (hypopnea). Both types of events have similar pathophysiology and are generally considered to be equal with respect to their impact on patients. There are several methods of quantifying the severity of the disorder such as measuring the number of apneas and hypopneas per hour of sleep (the apnea-hypopnea index: AHI), the severity of oxygen desatFrom the

Relationship between C-reactive protein levels and obstructive sleep apnea syndrome

“…It has been suggested that even slight increases in the apnea hypopnea index (AHI) can lead to increased mortality from cardiovascular diseases. Inflammation plays a fundamental role in the development of atherosclerosis (Kokturk et al, 2005), and the inflammatory marker C-reactive protein (CRP) can be used as a potential diagnostic tool. Studies have demonstrated that in individuals with coronary atherosclerotic heart disease, diabetes, hypertension, or those that smoke, CRP is increased as compared with that in the normal population.…”

Obstructive sleep apnea syndrome and cardiovascular disease: The influence of C-reactive protein

“…The serum CRP levels were significantly higher in the OSA group than in the control group In multiple regression analysis, elevated hs-CRP levels were associated with AHI which was independent of obesity Kokturk et al [20] 94 OSAS patients 57 controls CRP and conventional cardiovascular risk factors such as total cholesterol, low-density lipoprotein, high-density lipoprotein, very low density lipoprotein, and triglycerides CRP levels were significantly elevated in the OSAS group compared to the non-OSAS group CRP levels were independently associated with AHI Shamsuzzaman et al [19] 22 OSAS patients 20 controls CRP CRP levels were independently associated with OSA severity…”

“…A previous metaanalysis showed PAP therapy to significantly reduce CRP factors such as obesity, other CVDs and medications. Although, several studies have indicated independent associations between CRP levels and OSAS [19][20][21][22][23][36][37][38] , others do not demonstrate significant correlations after adjustment for associated confounding variables [39][40][41][42] . It is possible that OSAS alone may not contribute substantially to CVD since multiple factors have been implicated in the occurrence of CVDs in high-risk patients.…”

“…Factors such as sample size, statistical methodology and study design could be responsible for this disparity. Most of the studies to date [19][20][21][22] presented elevated CRP levels in OSAS patients; however the role of obesity and sleep duration in this CRP elevation has been questioned by other studies [20,23] . Therefore, as the role of CRP as a risk factor in OSAS is open to discussion, one could speculate that CRP's value as a special marker of OSASrelated cardiovascular risk is attenuated.…”

The correlation of ECHO findings of right cardiac pathologies with BNP, uric acid, and CRP in OSAS

“…CRP levels have been shown to be higher in patients with OSAS together with cardiovascular diseases compared to those who have OSAS without cardiovascular diseases (14). B-type brain natriuretic peptide (BNP) production from the heart is induced because of the hypoxia and sympathetic discharge.…”